Influenza poses a heavy burden to our health service. The WHO estimates that seasonal
influenza causes 250,000-500,000 deaths worldwide each year. Various strategies including
intradermal vaccination and new vaccine adjuvants have been shown to improve immunogenicity.
Recently, imiquimod, a synthetic Toll-like receptor 7 (TLR7) agonist useful for the treatment
of DNA virus infection, have been shown to improve vaccine immunogenicity against influenza
virus in mouse model. The objective of this prospective double-blind randomized controlled
trial is to evaluate the effect and safety of topical treatment with imiquimod immediately
before intradermal influenza vaccination in healthy young adults.